Hello experts, Is it polite/ethical for HR or Recruiting officer not to get across to you after interview on performance and outcome?

It's absolutely your right to ask for a feedback about the Cv you applied, or the interview you had.

This will help to know weaknesses, and to improve my skills, if the reason was that I am unqualified for specific vacancy.

On the other hand, if the reason was that I am overqualified, that will make find new approaches to find suitable vacancies.